Patent literature describes a number of rescue devices and systems that use avalanche airbags to bring the user of such device or system to the surface of the avalanche debris. Folding airbags are preferably attached to a backpack or a harness on the user's shoulders or around the waist. The device is equipped with a pressurized gas cartridge, the gas preferably being carbon dioxide, the cartridge being connected via valves with a bag that is inflated in case of emergency.
Swiss patent CH 705341 describes a rescue device with foldable single-chamber airbag provided with an inner skeleton made of material of high tear strength. The airbag is connected via special valves of proprietary design to two cartridges filled with pressurized carbon dioxide. During an avalanche descent the airbag is automatically filled with gas and surrounds the user's neck and back.
Another solution is presented in U.S. Pat. No. 7,878,141. The device comprises a folded balloon placed in a pocket and an arrangement for inflating the balloon with a mixture of gas and ambient air. The inflating arrangement comprises a pressure gas cylinder connected via a check valve with a high-pressure tubing and an ejector to which ambient air is drawn in through an air intake. Elements of the device and the backpack are attached to a harness which comprises a panel, shoulder straps and a buckled waist belt. In case of emergency the airbag is inflated forming a single-compartment balloon that surrounds the backpack.